Forget it. I'll never give in.

休想，我不会让步的。

Never give up and never give in.

永远不要放弃，永远不要屈服。

I'll never give in, she thought.

我永远也不会屈服，她想。

Never give in to pessimism.

千万不要悲观。

Never give in to pessimism.

千万不要屈服于悲观。